Zerobandgap

Zerobandgap refers to a specific electronic band structure in solid-state physics where the conduction band and valence band edges meet at the same energy level. This unique characteristic means there is no energy gap between these two bands. In a typical semiconductor, a band gap exists, requiring electrons to absorb a minimum amount of energy to jump from the valence band to the conduction band, thereby enabling electrical conductivity. In a zerobandgap material, however, electrons can move between these bands with very little or no energy input.

This absence of a band gap leads to peculiar electronic and optical properties. Zerobandgap materials often exhibit high electrical conductivity, behaving more like metals than semiconductors. However, their conductivity can be precisely tuned through doping or by applying external stimuli like strain or electric fields. This tunability makes them attractive for various applications.

A prominent example of a zerobandgap material is graphene, a single layer of carbon atoms arranged in a hexagonal lattice. Its unique electronic structure, where electrons behave as massless Dirac fermions, gives rise to exceptional electrical and thermal conductivity. Other materials, such as certain topological insulators and some semimetals, also possess zerobandgap characteristics. The study of zerobandgap materials is an active area of research, driven by the potential for novel electronic devices, sensors, and energy harvesting technologies.